[Cryptography] Bizarre behavior of a non-smart mobile phone

mok-kong shen mok-kong.shen at t-online.de
Sun May 14 18:30:53 EDT 2017

Am 14.05.2017 um 09:37 schrieb Ray Dillinger:
> On 05/13/2017 02:05 PM, mok-kong shen wrote:
>> Am 10.05.2017 um 21:00 schrieb mok-kong shen:
>> [snip]
>>> Being a layman in such issues, I should be very grateful for exact
>>> explanations of the phenomena.
>> I like to add that I am mainly interested in technical explanations of
>> the phenomena, i.e. whether
>> it is indeed true, and how, that the SIM card in my mobile phone got
>> manipulated, and personally
>> deem it not favorable, nor essential, realistic, etc. to conjecture in
>> our group on the motivations
>> behind such manipulations, if these indeed happened,
> This does not seem like a thing that could be done by manipulation
> of the SIM card alone.  Among other things, the SIM card is not a
> device that stores the phone numbers of your contact list.
One has the option of storing the contact list either on the SIM card or 
on the device.
Storing on the SIM card has the advantage that, if one migrates to a new 
device, there
is no need of building up a new contact list.

But actually whether the manipulation is done on the SIM card or done 
on the device itself is not essential. Essential in the present context 
is IMHO the fact
that there is a standing connection between the SIM card provider and 
the device
(necessary at least for accounting purposes) which I guess could be 
attacked by a
capable hacker.
> The behavior you describe would happen only as a result of bad
> firmware or drivers in the device, or as a result of a bad device.
> We can wonder why the firmware, drivers, or device is bad, but
> I can't think of any reason why anyone benefits from this behavior
> so I doubt that it's a deliberate act unless the motive is pure
> malice.  Malice does not usually suffice to motivate something as
> complicated as that behavior, when it would be far easier to just
> deactivate the SIM card and leave you with a bricked phone.  And
> I don't know your situation, but I hope that you haven't got
> anyone harboring that degree of malice against you.
Sorry, I don't understand your logic. If the malice could even 
deactivate the SIM card
as such, why couldn't he (in my view) just as simply manage do the 
things I described?
After all, deactivating the SIM card means that the device will be no 
longer be operational,
which wouldn't be a very favorable goal of the hacker.

M. K. Shen

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